Martin Freeman says there are not enough police officers on UK streets.

The 47-year-old actor plays a real-life former officer, Detective Superintendent Stephen Fulcher, who quit the force in 2014 after being disciplined for gross misconduct for breaching police protocol to catch killer Christopher Halliwell, in 'A Confession'.

Fulcher arrested Halliwell in 2011 for the murder of Sian O'Callaghan and also got him to confess to killing Becky Godden years earlier and Martin believes Fulcher was unfairly treated.

He told the Daily Mirror newspaper: ''It's one of those things where you go, 'I can't believe that. He's been properly done there'. And not only has he been done, but it's someone who you really do want working for us.

''There aren't enough police on the ground. You're going to get rid of good ones as well? It's a very dodgy road to go down, I think, for us as a society.''

Martin previously insisted he wasn't nervous about the potential controversies in telling the story of Detective Superintendent Fulcher and he thinks Jeff Pope's six part ITV true crime drama has found ''a very human way'' of dealing with things.

He said: ''I think sometimes I've been wrong not to feel that [wariness], in the past. I've taken decisions in my professional life where, in hindsight - not many, but occasionally in hindsight - where I probably should have thought of that.

''Someone will be offended by this. Some will think we've gone too far, or not far enough. But for me, it's a very human way of telling the story of... well, obviously the tragedy is young women being murdered. That's the real tragedy.

''But beyond that, secondary to that, is the tragedy that Steve Fulcher and his family went through. He was a man trying to do the right thing, and he paid a very, very high price for it.''

DI Fulcher resigned after failing to caution Halliwell and interrogating him without legal representation present, and although these actions compromised the subsequent court case, the confession did mean the killer was jailed for the murders of Becky and Sian.

Martin added: ''My sympathy and my empathy is certainly with Steve Fulcher, let's put it that way, and not just because I've played him. I don't know how anyone could say he did the wrong thing, morally.

''I'm also somebody who believes passionately that police have to be accountable. Of course they do. But still, morally, I'd much rather coppers like him were out there.''